674636561 has 2 divisors, whose sum is σ = 674636562. Its totient is φ = 674636560.

The previous prime is 674636489. The next prime is 674636569. The reversal of 674636561 is 165636476.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 626250625 + 48385936 = 25025^2 + 6956^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-674636561 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (674636569) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 337318280 + 337318281.

It is an arithmetic number, because the mean of its divisors is an integer number (337318281).

Almost surely, 2^674636561 is an apocalyptic number.

It is an amenable number.

674636561 is a deficient number, since it is larger than the sum of its proper divisors (1).

674636561 is an equidigital number, since it uses as much as digits as its factorization.

674636561 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 544320, while the sum is 44.

The square root of 674636561 is about 25973.7667849698. The cubic root of 674636561 is about 877.0478558536.

The spelling of 674636561 in words is "six hundred seventy-four million, six hundred thirty-six thousand, five hundred sixty-one".